Foldable bicycle pedal crank

ABSTRACT

A foldable bicycle pedal crank, comprising a crank, a crank endpiece, a lock, and a pedal. The crank has a connecting yoke, passed through by a first crank hole and second crank holes which aim across an indentation thereof. The crank endpiece has an insertion part that is inserted in the indentation, with a first hole, second holes and a third hole passing through the insertion part. The lock further comprises a lock body, at least one first bolt and second bolts. The first and second bolts have outer ends connected with the lock body. The first bolt further has an inner end and is hollow, enclosing a space that towards the inner end is limited by a step and accommodates a rod. The rod has a far end that passes through the inner end of the first bolt and is fixed. A spring surrounds the rod, leaning against the step. The pedal is connected with the crank endpiece.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a foldable bicycle pedal crank, particularly to a foldable bicycle pedal crank that is folded quickly and conveniently allowing maximum use of space.

[0003] 2. Description of Related Art

[0004] Bicycles have been a traditional means of moving and in addition have become a modern tool of sports and leisure, enhancing quality of life. Therefore, bicycles are popular today. For convenience at home as well as on travel, bicycle volumes have been shrunk. Most importantly, foldable bicycles have been developed, allowing to transport bicycles in cars for increased flexibility. After folding a bicycle, each folded part needs to take as much advantage of space as possible to minimize volume. Still, pedals mounted on cranks extending outward on both sides of the bicycle are difficult to fold by 180 degrees to take advantage of the space between the cranks and the bicycle frame, so conventional designs have the pedals stand up or point down. Standing pedals, however, are placed outside of the cranks, increasing width of the folded bicycle, while pedals that point down extend downward, not fully taking advantage of empty space within the bicycle frame. Furthermore, for folding a conventional foldable bicycle, often a tool is needed, making folding the bicycle awkward and complicated.

SUMMARY OF THE INVENTION

[0005] It is the main object of the present invention to provide a foldable bicycle pedal crank which allows to take considerable advantage of space and to fold the pedal at an optimum location for minimizing the volume of the folded bicycle.

[0006] Another object of the present invention is to provide a foldable bicycle pedal crank which allows to fold away the pedal simply, precisely and fast.

[0007] A further object of the present invention is to provide a foldable bicycle pedal crank which is novel, being different from foldable bicycle pedal cranks currently used.

[0008] The present invention can be more fully understood by reference to the following description and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009]FIG. 1 is an exploded perspective view of the foldable bicycle pedal crank of the present invention.

[0010]FIG. 2 is a perspective view of the foldable bicycle pedal crank of the present invention when assembled.

[0011]FIG. 3 is a sectional side view of the present invention.

[0012]FIG. 4 is a schematic illustration of using the present invention.

[0013]FIG. 5 is a schematic illustration of the present invention when not folded.

[0014]FIG. 6 is a schematic illustration of the present invention when folded.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0015] As shown in FIGS. 1 and 2, the foldable bicycle pedal crank of the present invention mainly comprises: a crank 1; a crank endpiece 2; a lock 3; and a pedal 4. The crank has a static end connected to a bicycle frame by a connecting hole 11, as shown in FIG. 5, and a far end with a connecting yoke 12. The connecting yoke 12 has a central indentation 13 for taking in the crank endpiece 2. A first crank hole 14 and two second crank holes 15 on two sides of the first crank hole 14 are bored through the connecting yoke 12, aiming across the indentation 13, and have widened end segments 141, 151. The crank endpiece 2 has an insertion part 21, inserted in the indentation 13. A first hole 22, two second holes 23 and a third hole 24 are bored through the insertion part 21. The two second holes 23 are placed on two opposite sides of the first hole 22. The third hole 24 is placed at a third side of the first hole 22 perpendicular thereto. The first, second and third holes 22, 23, 24 have widened end segments 221, 231, 241, respectively. The insertion part 21 has a curved top side 25, allowing to turn the insertion part 21 within the indentation 13. On a far end, opposite to the insertion part 21, a connecting hole 26 is bored through the crank endpiece 2, perpendicularly oriented to the first hole 22 and allowing to fasten the pedal 4. The lock 3 comprises a lock body 31, a first bolt 35 and two second bolts 36. A first threaded hole 32 and two second threaded holes 33 on two sides of the first threaded hole 32 are bored through the lock body 31. The lock body 31 has an outer grooved surface 34 with peripheral grooves for easy gripping and pulling thereof. The two second bolts 36 are placed on two sides of the first bolt 35. The first and second bolts 35, 36 have threaded outer ends 351, 361 which are screwed into the first and second threaded holes 32, 33, respectively, as shown in FIG. 3. Furthermore, the first and second bolts 35, 36 have inner ends 354, 364 that fit into the widened end segments 221, 231, 241 of the first, second and third holes 22, 23, 24. The first bolt 35 is a hollow body, enclosing a space 352 that is limited by a step 353. A rod 37 is inserted in the space 352 having an outer end with a head 371 and an inner threaded end 372. The head 371 and the space 352 have equal diameters. A hexagonal hole 373 is cut into the head 371. A spring 38 is laid around the rod 37, leaning against the step 353 and, opposite thereto, against the head 371. The second bolts 36 on the inner ends thereof have slits 362, allowing to screw the second bolts 36 into the second threaded holes 32. A nut 39 is set on the rod 37, having a cavity 391 and a thread 392. The cavity 391 takes in the inner end of the first bolt 35, while the thread 392 engages with the threaded end 372 of the rod 37. The pedal 4 has a connecting rod 41 which passes through the connecting hole 26 of the crank endpiece 2.

[0016] For assembling the foldable bicycle pedal crank of the present invention, the first and second bolts 35, 36 of the lock 3 are respectively inserted into the first and second crank holes 14, 15 of the crank 1 and put through the first and second holes 22, 23 of the crank endpiece 2. The nut 39 is screwed tight on the threaded end 372 of the rod 37, finishing assembly.

[0017] Referring now to FIGS. 4 and 5, for folding up the pedal 4, the lock body 31 is pulled outward, as indicated in FIG. 4. Accordingly, the first and second bolts 35, 36 move along, with the second bolts 35 leaving the indentation 13, allowing the crank endpiece 2 to be turned with the rod 37 as an axis. Since the rod 37 is held back by the nut 39, the first bolt is shifted relative to the rod 37, compressing the spring 38. At this time the crank endpiece 2 is free to be turned around the rod 37. Turning thereof by 90 degrees and releasing the lock body 31 causes the spring 38 to drive the bolt 35 back into the first hole 22, with one of the second bolts 36 entering the third hole 24, as shown in FIG. 6. In this state, the crank endpiece 2 is locked again, with the pedal moved into empty space of the bicycle frame. Since the inner ends 354, 364 of the first end second bolts 35, 36 fit into the widened end sections 221, 231, 241 of the first, second and third holes 22, 23, 24, pushing back of the first end second bolts 35, 36 proceeds smoothly. Furthermore, the first bolt 35 has a length that ensures that, when the lock body 31 is pulled outward, the first bolt 35 does not leave the first hole 22 and the insertion part 21, so that one of the second bolts 36 is readily pushed into the third hole 24.

[0018] The present invention allows by pulling out and releasing the lock 3 conveniently to turn and fix again the crank endpiece 2 for folding the pedal 4 into a most preferable position in which the bicycle has no excessive width and in which empty space between the crank and the bicycle frame is taken advantage of. Thus a maximum effect of minimizing volume is achieved.

[0019] While the invention has been described with reference to a preferred embodiment thereof, it is to be understood that modifications or variations may be easily made without departing from the spirit of this invention which is defined by the appended claims. 

1. A foldable bicycle pedal crank, comprising: a crank, having a far end with a connecting yoke, which is passed through by a first crank hole and second crank holes, aiming across an indentation thereof; a crank endpiece, having an end with an insertion part that is inserted in said indentation, with a first hole, second holes and a third hole passing through said insertion part; a lock, further comprising a lock body, at least one first bolt which has an outer end connected with said lock body and an inner end opposite thereto and which is hollow, enclosing a space that towards said inner end is limited by a step and accommodates a rod with a far end that passes through said inner end of said first bolt and is fixed, with a spring surrounding said rod, leaning against said step, and second bolts which have outer ends connected with said lock body; and a pedal, connected with said crank endpiece.
 2. A foldable bicycle pedal crank according to claim 1, wherein said crank on a static end opposite to said far end has a connecting hole for connecting with a bicycle frame.
 3. A foldable bicycle pedal crank according to claim 1, wherein said second crank holes are located at two opposite sides of said first crank hole.
 4. A foldable bicycle pedal crank according to claim 1, wherein said second holes are located at two opposite sides of said first hole.
 5. A foldable bicycle pedal crank according to claim 1, wherein said third hole is placed on one side of a line between said first hole and said second holes.
 6. A foldable bicycle pedal crank according to claim 1, wherein said crank endpiece has a curved top side, allowing to be turned within said indentation.
 7. A foldable bicycle pedal crank according to claim 1, wherein said rod on said far end thereof at a section outside of said first bolt is threaded, allowing to fix said rod by a nut.
 8. A foldable bicycle pedal crank according to claim 1, wherein said crank endpiece at an end opposite to said insertion part has a connecting hole for connecting with said pedal.
 9. A foldable bicycle pedal crank according to claim 1, wherein said lock body has an outer side with peripheral grooves for manual pulling and pushing of said lock.
 10. A foldable bicycle pedal crank according to claim 1, wherein said lock body has a first threaded hole and second threaded holes and said first and second bolts on said outer ends thereof have threads, engaging with said first and second threaded holes.
 11. A foldable bicycle pedal crank according to claim 1, wherein said rod has a head, with said spring being inserted between said head and said step of said first bolt.
 12. A foldable bicycle pedal crank according to claim 11, wherein said head of said rod has a hole for holding and screwing said rod.
 13. A foldable bicycle pedal crank according to claim 1, wherein said second bolts have inner ends opposite to said outer ends thereof, with slits being cut into said inner ends for screwing said second bolts.
 14. A foldable bicycle pedal crank according to claim 1, wherein said pedal has a connecting rod for connecting with said connecting hole.
 15. A foldable bicycle pedal crank according to claim 1, wherein said first, second and third holes have widened end segments.
 16. A foldable bicycle pedal crank according to claim 1, wherein said first and second crank holes have widened end segments.
 17. A foldable bicycle pedal crank according to claim 7, wherein said nut has a cavity for accommodating said inner end of said first bolt. 